Selenium Supplements

Considerable research and studies are underway on the need and benefits of selenium supplements. The subject of recent study and debate is the role of selenium in cancer prevention.

Selenium

Selenium is a trace material that is essential in several metabolic pathways. It is found in soil, water and some foods. The mineral is incorporated into proteins to make selenoproteins, an important antioxidant enzyme. This antioxidant helps prevent cellular damage from free radicals, a by-product of oxygen metabolism that contributes to the development of chronic diseases like cancer and heart disease. Apart from playing an important role in the immune system, selenoproteins also help regulate the thyroid function.

Selenium Deficiency

Selenium deficiency is rare in US. However, it is witnessed in other countries, especially in China, where soil concentration of selenium is low. Selenium deficiency may lead to hypothyroidism, weakened immune system. Evidences indicate that selenium deficiency may lead to the following specific diseases in human.

• Keshan Disease that leads to enlarged heart and poor heart function, especially in selenium-deficient children.
  
  
• Kashin-Beck Disease, which results in osteoarthropathy
  
  
• Myxedematous Endemic Cretinism that results in mental retardation
  
  

The major causes for selenium deficiencies include gastrointestinal disorders and processed or refined foods. Selenium deficiency is also seen in patients on total parenteral nutrition (TPN) as their source of nutrition.

Uses of Selenium Supplements

Selenium supplements are useful to human race in a variety of ways. Few of them are tested and proved with scientific evidence while others uses are unclear for which the scientific studies still underway.

Uses with scientific evidence

As Antioxidan: Selenium is a key trace element that has antioxidant properties in humans.

Prevention of Prostate Cancer: A study conducted by Nutritional Prevention of Cancer (NPC) suggests that selenium supplementation reduces the risk of prostate cancer among men with PSA (prostate specific antigen) levels and low selenium blood levels. However, the study indicates that selenium did not reduce the risk of lung, colorectal, or basal cell carcinoma of the skin, rather increased the risk of squamous cell skin carcinoma.

Unclear uses of Selenium that lack scientific evidence

Asthma: Few studies report that selenium supplements may help asthma symptoms. However, there is no clear scientific evidence on the same.

Cancer Treatment: Physicians opine that people with cancer have low levels of selenium. However, the reason for this deficiency is still a mystery. Studies are underway to determine the effect of selenium on both cancer prevention and cancer treatment.

Cardiovascular Disease Prevention Research is underway to study the antioxidant property of selenium, which should help in the prevention of heart disease and other cardiovascular conditions.

Chemotherapy: A strong contradiction exists between selenium and chemotherapy. Because there are mixed opinions on the use of selenium supplements in patients undergoing chemotherapy for cancer.

Selenium Supplements

Plant foods are rich in selenium, especially the ones that grow in selenium rich soil. For instance, researchers say that soil in the high plains of northern Nebraska and the Dakotas has high levels of selenium. The soil in certain parts of China and Russia has rather low levels of selenium. Meats and seafood are also rich sources of dietary selenium. Other foods that are rich in selenium supplements include

• Brewer's yeast
  
• Wheat gram
  
• Butter
  
• Brazil nuts
  
• Garlic
  
• Grains
  
• Sunflower seeds
  
• Walnuts
  
• Raisins
  
• Liver
  
• Kidneys
  
• Shellfish
  
• Fish
  
• Cooked beef
  
• Spaghetti
  
• Cottage cheese
  
• Oatmeal
  
• Cheddar cheese
  
• Brown and white rice
  
  

Side effects of high selenium levels

People with high levels of selenium are at the increased risk of developing selenosis. Selenosis may lead to

• Gastrointestinal troubles like nausea, vomiting, abdominal pain, diarrhea, garlic-like breath odor, and metallic taste.
  
  
• Neuromuscular-psychiatric disturbances including weakness/fatigue, lightheadedness, irritability, hyperreflexia, muscle tenderness, tremor, and peripheral neuropathy
  
  
• Dermatologic changes like skin rash, dermatitis, flushing, fingernail loss and hair loss.
  
  
• Liver dysfunction
  
  
• Kidney dysfunction
  
  
• Thrombocytopenia or low blood platelets
  
  
• Immune alterations or cell impairment
  
  
• Thyroid dysfunction
  
  
• Reduced sperm motility, or growth retardation.